The present invention relates to a food intake restriction apparatus and method. More specifically, the invention relates to a food intake restriction apparatus and method for surgical application in the abdomen of a patient for forming an upper pouch and a stoma opening in the stomach or esophagus. The term patient includes an animal or a human being.
Food intake restriction apparatus in the form of a gastric banding device, in which a band encircles a portion of a patient""s stomach to restrict the food intake of the patient, have been used in surgery for morbid obesity to form a small gastric pouch above the band and a reduced stoma opening in the stomach. Although such a band is applied around the stomach to obtain an optimal stoma opening during surgery, some prior gastric banding devices are provided with an adjustment means enabling a minor post-operation adjustment of the size of the stoma opening. In all such prior art devices such as disclosed in U.S. Pat. No. 4,592,339, European Patent No. 0611561 and International Patent Application WO 94/27504, the adjustment means typically comprises an inflatable cavity in the band and an injection port in fluid connection with the inflatable cavity for adding fluid to or withdrawing fluid from the latter. In practice, the band is made of silicone rubber which is a material approved for implantation and the fluid is a liquid such as an isotonic salt solution.
It has also been found that the volume of the gastric pouch above the band increases in size up to ten times after operation. Therefore the pouch volume during surgery needs to be very small, approximately 7 ml. To enable the patient to feed the stomach with sufficient nutrition immediately after an operation considering such a small gastric pouch, the stoma initially needs to be relatively large and later needs to be substantially reduced, as the pouch volume increases. To be able to achieve a significant range of adjustment of the band, the cavity in the band has to be relatively large and is defined by a thin flexible wall, normally made of silicone material. Furthermore, the size of the stoma opening has to be gradually reduced during the first year after surgery as the gastric pouch increases in size. As indicated above, the reduction of the stoma opening using the prior art devices is achieved by adding liquid to the cavity of the band via the injection port to expand the band radially inwardly.
A great disadvantage of repeatedly injecting liquid via the injection port is the increased risk of the patient getting an infection in the body area surrounding the injection port. If such an infection occurs the injection port has to be surgically removed from the patient. Moreover, such an infection might be spread along the tube interconnecting the injection port and the band to the stomach, causing even more serious complications. Thus, the stomach might be infected where it is in contact with the band, which might result in the band migrating through the wall of the stomach. Also, it is uncomfortable for the patient when the necessary, often many, post-operation adjustments of the stoma opening are carried out using an injection needle penetrating the skin of the patient into the injection port.
It may happen that the patient swallows pieces of food too large to pass through the restricted stoma opening. If that occurs the patient has to visit a doctor who can remove the food pieces, if the band design so permits, by withdrawing some liquid from the band to enlarge the stoma opening to allow the food pieces to pass the stoma. Then, the doctor has to add liquid to the band in order to regain the restricted stoma opening. Again, these measures require the use of an injection needle penetrating the skin of the patient, which is uncomfortable for the patient.
An object of the invention is to provide a food intake restriction apparatus for forming a stoma opening in the stomach or esophagus of a patient which permits regular post-operation adjustments that are comfortable for the patient.
Another object of the present invention to provide a new food intake restriction which is easy to adjust and does not require the use of an injection needle for accomplishing post-operation adjustments of the stoma opening.
Accordingly, there is provided a food intake restriction apparatus, comprising an operable restriction device implanted in a patient and engaging the stomach or esophagus to form an upper pouch and a restricted stoma opening in the stomach or esophagus, a source of energy for energizing the restriction device, and a control device operable from outside the patient""s body for releasing energy from the source of energy, wherein the released energy is used in connection with the operation of the restriction device.
As a result, the advantage is achieved that the implanted restriction device can be non-invasively operated, when the restriction device has to be adjusted. Furthermore, the apparatus of the invention provides a simple and effective control of the energy supplied to implanted components of the apparatus which ensures an extended and reliable functionality of the apparatus, possibly for the rest of the patient""s natural life, and at lest many years.
The restriction device preferably controls the size of the stoma opening. This may allow the patient to temporarily open up the stoma opening to remove food pieces stuck therein.
The control device may also control the restriction device. The control device may comprise an internal control unit, preferably including a microprocessor, implanted in the patient for controlling the restriction device. The control device may further comprise an external control unit outside the patient""s body, wherein the internal control unit is programmable by the external control unit, for example for controlling the restriction device over time. Alternatively, the internal control unit may control the restriction device over time in accordance with an activity schedule program, which may be adapted to the patient""s needs.
Conveniently, the external control unit may load the internal control unit with data in accordance with a loading mode only authorized for a doctor. For specialized controls of the restriction device, the external control unit may control the internal control unit in accordance with a doctor mode, only authorized for the doctor. For simple controls of the restriction device, the external control unit may control the internal control unit in accordance with a patient mode permitted for the patient. Thus, by using the external control unit in accordance with different modes it is possible to have certain functions of the restriction device controlled by the patient and other more advanced functions controlled by the doctor resulting, which enables a flexible post-operation treatment of the patient.
Generally, the apparatus further comprises an operation device implanted in the patient for operating the restriction device, wherein the control device controls the operation device to operate the restriction device. The control device may directly power the operation device with energy released from the source of energy and/or power other implanted energy consuming components of the apparatus. The term directly is used to mean, on one hand, that the operation device is powered with released energy while the latter is being released by the control device, on the other hand, that the released energy may be somewhat delayed, in the order of seconds, by for instance an energy stabilizer before powering the operation device. The advantage of directly using energy as it is released is that the apparatus can be of a very simple design and the few components involved makes the apparatus extremely reliable.
The restriction device may be non-inflatable, i.e. with no hydraulic fluid involved for the adjustments of the restriction device. This eliminates problems with fluid leaking from the restriction.
The operation device may comprise hydraulic means and at least one valve for controlling a fluid flow in the hydraulic means. The control device may suitably comprise a wireless remote control for controlling the valve. The restriction device may comprise hydraulic means and the operation device may comprise a reservoir forming a fluid chamber with a variable volume connected to the hydraulic means. The operation device may distribute fluid from the chamber to the hydraulic means by reduction of the volume of the chamber and withdraw fluid from the hydraulic means to the chamber by expansion of the volume of the chamber.
In accordance with a first main aspect of the invention, the source of energy is external to the patient""s body and the control device releases wireless energy from the source of energy. An energy storage device, preferably an electric accumulator, may be implanted in the patient for storing the wireless energy released from the external source of energy. The electric accumulator may comprise at least one capacitor or at least one rechargeable battery, or a combination of at least one capacitor and at least one rechargeable battery. Alternatively, a battery may be implanted in the patient for supplying electric energy to implanted electric energy consuming components of the apparatus, in addition to the supply of wireless energy. Where the control device comprises an implanted control unit the electronic circuit thereof and the restriction device may be directly powered with transformed wireless energy, or energy from either the implanted energy storage device or battery.
In a first particular embodiment in accordance with the first main aspect of the invention, the operation device comprises a motor, preferably an electric motor which may have electrically conductive parts made of plastics. The motor may include a rotary motor, wherein the control device is adapted to control the rotary motor to rotate a desired number of revolutions. Alternatively, the motor may include a linear motor, or a hydraulic or pneumatic fluid motor, wherein the control device is adapted to control the fluid flow through the fluid motor. Motors currently available on the market are getting smaller and smaller. Furthermore, there is a great variety of control methods and miniaturized control equipment available. For example, a number of revolutions of a rotary motor may be analyzed by a Hall-element just a few mm in size.
In a second particular embodiment in accordance with the first main aspect of the invention, the control device is adapted to shift polarity of the released energy to reverse the operation device. The operation device may suitably comprise an electric motor and the released energy may comprise electric energy.
In a third particular embodiment in accordance with the first main aspect of the invention, the restriction device is operable to perform a reversible function and there is a reversing device implanted in the patient for reversing the function performed by the restriction device. Such a reversing function preferably involves enlarging and restricting the food passageway by the restriction device, suitably in a stepless manner. In this connection, the control device suitably controls the reversing device, which may include a switch, to reverse the function performed by the restriction device. The reversing device may comprise hydraulic means including a valve for shifting the flow direction of a fluid in the hydraulic means. Alternatively, the reversing device may comprise a mechanical reversing device, such as a switch or a gear box.
Where the reversing device comprises a switch the control device suitably controls the operation of the switch by shifting polarity of released energy supplied to the switch. The switch may comprise an electric switch and the source of energy may supply electric energy for the operation of the switch. The switch mentioned above may comprise an electronic switch or, where applicable, a mechanical switch.
In accordance with the third particular embodiment, the operation device preferably comprises a motor, wherein the reversing device reverses the motor.
In a fourth particular embodiment in accordance with the first main aspect of the invention, the restriction device comprises hydraulic means, for example including an expansible/contractible cavity for fluid. The operation device preferably comprises a pump for pumping a fluid in the hydraulic means, a motor for driving the pump, a valveless fluid conduit between the pump and the hydraulic means of the restriction device, and a reservoir for fluid, wherein the reservoir forms part of the conduit. All of the hydraulic components involved are preferably devoid of any non-return valve. This is of great advantage, because with valves involved there is always a risk of malfunction due to improperly working valves, especially when long time periods passes between valve operations. The reservoir may form a fluid chamber with a variable volume, and the pump may distribute fluid from the chamber to the hydraulic means of the restriction device by reduction of the volume of the chamber and withdraw fluid from the hydraulic means to the chamber by expansion of the volume of the chamber.
In accordance with a second main aspect of the invention, the source of energy is implanted in the patient. Thus, the control device releases energy from the implanted source of energy from outside the patient""s body. This solution is advantageous for embodiments of the apparatus that have a relatively high energy consumption which cannot be satisfied by direct supply of wireless energy.
The source of energy thus implanted may comprise an accumulator, preferably an electric source of energy, such as a battery having a life-time of at least 10 years.
The above first, second, third and fourth particular embodiments described in connection with the first main aspect of the invention are also applicable in accordance with the second main aspect of the invention, i.e. where the source of energy is implanted.
All of the above embodiments may be combined with at least one implanted sensor for sensing at least one physical parameter of the patient, wherein the control device may control the restriction device in response to signals from the sensor. For example, the sensor may comprise a pressure sensor for directly or indirectly sensing the pressure in the stomach. The expression xe2x80x9cindirectly sensing the pressure in the food stomachxe2x80x9d should be understood to encompass the cases where the sensor senses the pressure against the restriction device or human tissue of the patient. The pressure sensor may be any suitable known or conventional pressure sensor such as shown in U.S. Pat. Nos. 5,540,731, 4,846,181, 4,738,267, 4,571,749, 4,407,296 or 3,939,823; or an NPC-102 Medical Angioplasty Sensor. Where the control device comprises an internal control unit implanted in the patient, the internal control unit may suitably directly control the restriction device in response to signals from the sensor. In response to signals from the sensor, for example pressure, the patient""s position or any other important physical parameter, the internal control unit may send information thereon to outside the patient""s body. The control unit may also automatically control the restriction device in response to signals from the sensor.
Where the control device comprises an external control unit outside the patient""s body, the external control unit may, suitably directly, control the restriction device in response to signals by the sensor. The external control unit may store information on the physical parameter sensed by the sensor and may be manually operated to control the restriction device based on the stored information. In addition, there may be at least one implanted sender for sending information on the physical parameter sensed by the sensor.
An external data communicator may be provided outside the patient""s body and an internal data communicator may be implanted in the patient for communicating with the external communicator. The implanted communicator may feed data related to the patient, or related to the implanted restriction device, back to the external communicator. Alternatively or in combination, the external communicator may feed data to the internal communicator. The implanted communicator may suitably feed data related to at least one physical signal of the patient.
Generally, the apparatus of the invention may comprise a switch implanted in the patient for directly or indirectly switching the energy released from the source of energy. The restriction device may control the size of the stoma opening in the stomach or esophagus. For example, the restriction device may be operable to open and close the stoma opening or may steplessly control the latter. A pressure sensor may be provided for directly or indirectly sensing the pressure in the stomach. The control device may control the restriction device in response to signals from the pressure sensor.
The restriction device may be non-inflatable, i.e. with no hydraulic fluid involved for the adjustments of the restriction device. This eliminates problems with fluid leaking from the restriction device.
The apparatus may comprise an implanted energy transfer device, wherein the control device releases electric energy and the energy transfer device transfers the electric energy into kinetic energy for, preferably direct, operation of the restriction device. Suitably, an implanted stabilizer, such as a capacitor or a rechargeable accumulator, or the like, may be provided for stabilizing the electric energy released by the control device. In addition, the control device may release energy for a determined time period or in a determined number of energy pulses. All of the above embodiments are preferably remote controlled. Thus, the control device advantageously comprises a wireless remote control transmitting at least one wireless control signal for controlling the restriction device. With such a remote control it will be possible to adapt the function of the apparatus to the patient""s need over a period of time, which is beneficial with respect to the treatment of the patient.
The wireless remote control may be capable of obtaining information on the condition of the implanted restriction device and of controlling the restriction device in response to the information. Also, The remote control may be capable of sending information related to the restriction device from inside the patient""s body to the outside thereof.
In a particular embodiment of the invention, the wireless remote control comprises at least one external signal transmitter or transceiver and at least one internal signal receiver or transceiver implanted in the patient. In another particular embodiment of the invention, the wireless remote control comprises at least one external signal receiver or transceiver and at least one internal signal transmitter or transceiver implanted in the patient.
The remote control may transmit a carrier signal for carrying the control signal, wherein the carrier signal is frequency, amplitude or frequency and amplitude modulated and is digital, analog or digital and analog. Also the control signal used with the carrier signal may be frequency, amplitude or frequency and amplitude modulated.
The control signal may comprise a wave signal, for example, a sound wave signal, such as an ultrasound wave signal, an electromagnetic wave signal, such as an infrared light signal, a visible light signal, an ultra violet light signal, a laser signal, a micro wave signal, a radio wave signal, an x-ray radiation signal, or a gamma radiation signal. Where applicable, two or more of the above signals may be combined.
The control signal may be digital or analog, and may comprise an electric or magnetic field. Suitably, the wireless remote control may transmit an electromagnetic carrier wave signal for carrying the digital or analog control signal. For example, use of an analog carrier wave signal carrying a digital control signal would give safe communication. The control signal may be transmitted in pulses by the wireless remote control.
In all of the above solutions, the control device advantageously releases energy from the source of energy in a non-invasive, mechanical or non-mechanical manner.
The control device may release magnetic, electromagnetic, kinetic or thermal energy, or non-magnetic, non-thermal, non-electromagnetic or non-kinetic energy.
Another object of the present invention is to provide methods for treating morbid obesity.
Accordingly, in accordance with a first alternative there is provided a method of treating morbid obesity, comprising the steps of implanting an operable restriction device in a patient in engagement with the stomach or the esophagus to form a restricted stoma in the stomach or esophagus, providing a source of energy for energizing the restriction device, and controlling the source of energy to release energy for use in connection with the operation of the restriction device. The method may further comprise using energy released from the source of energy to operate the restriction device to enlarge and reduce, respectively, the food pasageway.
In accordance with a second alternative there is provided a method of treating morbid obesity, comprising the steps of placing at least two laparascopical trocars in a patient""s body, inserting a dissecting tool through the trocars and dissecting an area of the stomach or esophagus, placing an operable restriction device in the dissected area, so that the restriction device engages the stomach or the esophagus to form a restricted stoma in the stomach or esophagus, implanting a source of energy in the patient, and controlling the implanted source of energy from outside the patients body to release energy for use in connection with the operation of the restriction device.
In accordance with a third alternative there is provided a method of treating morbid obesity, comprising the steps of placing at least two laparascopical trocars in a patient""s body, inserting a dissecting tool through the trocars and dissecting an area of the stomach or esophagus, implanting an operable restriction device in the dissected area in engagement with the stomach or esophagus to form a restricted stoma in the stomach or esophagus, implanting an energy transfer device in the patient, providing an external source of energy, controlling the external source of energy to release wireless energy, and transferring the wireless energy by the energy transfer device into energy suited for use in connection with the operation of the restriction device.